In the following snippet of code, I'm trying to use addClass and removeClass to do some stuff with a tiny slider menu. As per IE9's "Developer Tools", I can't seem to notice the class change take effect. Can someone explain to me why?

Code:
$('.content-bottom .toggle').click(function(){

   if($(this).hasClass('close')){
      console.log('a');
      $('.content-bottom').animate({right: 0},'slow');
      $(this).removeClass('close');//DOES NOT WORK IN IE9
      $(this).addClass('open');//DOES NOT WORK IN IE9
      return false;
   }
                
   if($(this).hasClass('open')){
      console.log('b');
      $('.content-bottom').animate({right:initialLegendRight}, 'slow');
      $(this).removeClass('open');//DOES NOT WORK IN IE9
      $(this).addClass('close');//DOES NOT WORK IN IE9
      return false;
   }

});